I went with the RO90 because of it being a multi use sander vs the DTS only having a single use . Thanks for the video, it's videos like yours that helps make a difference

So, I see two things. 1. the RO90 it looks like you can rotate the sandpaper 3 times on the RO90 since Im figuring the tip will wear out long before the rest of the paper so the RO90 paper will last longer. 2. the shorter DTS with the angled hose will get into tighter spaces. Tough choice still

Thanks for taking the time to do this. Exactly my dilemma. So great info to help my decision making , cheers

Thanks for the review. Am looking at both these sanders for delta sanding myself. Didn't realize the RO90 has the optional extension, but without dust extraction. Think I'm going to have to pick up both at a store to compare ergonomics.

I'm considering the DTS400 and one thing I think that it has in its' favour over the RO90 is that you can use it in more confined areas eg inside drawers because of its' shorter length. Having said that the extraction hose sticks out the back so I may need to use a 90 or 45 degree socket adapter for the hose. At the moment I have a Dewalt 26430 and a Bosch GOP multi tool which are delta sanders and these have the same limitation of being long - not that I sand inside a lot of drawers but it was just a thought for an upcoming project.

I built a door that has 4” panels recessed about 1/2” inside the main frame. I have both of the sanders in your review. They are both great, but neither of them would really sand in my 4” spaces. The DTS 400 would not fit at all, and the RO 90 was too bulky near the surface. The pad is small enough to fit, but there are too many plastic parts that protrude around the edges. I ended up finding a DX93 on eBay that had barely been used. In fact, the twist tie was still wrapped around the power cord. Absolutely thrilled! The DX worked perfectly!

Excellent overview thanks, I'm doing a complete external rennovation of a weatherboard house and have been trying to decide between an RO90 and the 400 to do window frames and compliment my Ro125 which is doing the bulk of the heavy lifting. Festool being my only real option due to dust control as some areas have underlying lead paint. this has given me all the info I need, many thanks.

t'would be nice to see the units in action to see how they work. That's what is missing here.

Thank you, this was super informative.

Thank you so much for your review…

Excellent review, thanks

I have the RO150 the RO90 the DTSC and the RTSC they are all brilliant.

Amazing video!

I have the DTS 400 and its great, could you recommend a festool sander within a similar price range to add next to my collection as i think the RO 90 is a bit too similar.

Are both using random orbital motion when set up as a delta sander, or do they just do simple oscillatory vibrations? If random orbit, did you notice a difference in the amplitude of the orbit...were either orbits large enough to be a problem for getting tight against an edge?

Thanks for sharing. Exactly the explanations and level of details I never managed to get from a Festool dealer. Agree with you I will go for the RO 90 too for all the acurate little sanding stuff. Cheers from France

I don't understand the conclusion at 07:14 'If you think about prices the RO90 is 30-50% higher in cost than the DTS400. I got this [RO90] a month old for the same price I could have got this.' So he got it second hand or something?

I just got the 90 and never feel like I am flat when using the 90mm or the delta. Of course it's been 40 days since buying.

The sanding area at the tip of the delta on one of these becomes clogged in about five minutes without vacuum and pills up in about ten minutes with it. You can't efficiently hold the Rotex flat. You don't hold the 400 on top as it's too unstable, you wind up holding it around the body. The edge protector is about keeping the edges of the pad in good shape, you should be protecting the work surface with your skill handling the machine not a plastic bumper. Most people take it off and leave it off as the compromise of not getting at the edge is not worth having it on and it blocks your view.

An advantage for the RO 90 is the delta disks can be rotated. As the leading point of the disk wears out you can simply rotate it. On the DTS they fit only one way.

Nothing about sanding quality and no demo either... wow

Nice review 👍 Spasibo